Refining of glyceride oils and recovery of by-products



Patented Feb. 4, 1947 REFINING OF GLYGERIDE OILS AND RECOVERY OF BY-PRODUCTS Morris Mattikow, New York, N. Y., assignor, by mesne assignments, to Benjamin Clayton,

Houston, Tex., Unincorporated doing business as Refining No Drawing. Application April 3, 1944,

Serial No. 529,394

Claims. (Cl. 260-210) This invention relates to the refining of glyceride oils and recovery of byproducts, and more particularly to a process in which valuable byproducts of the class usually grouped under the heading unsaponifiables are recovered as part of a refining operation. r

Glyceriole oils, particularly vegetable oils, contain a large number of materials other than the glycerides of fatty acidsthe latter being the main constituent constituting substantially all of the refined oil. The other materials include free fatty acids which are removed as soap in alkali refining operations, phosphatides which maybe either removed in an initial degumming step or as part of the soap stock in the alkali refining operation, and a class of materials above referred to as unsaponifiables, some of which remain in the refined oil and some of which are removed in the various refining steps such as degumming or alkali treating steps. The present invention is chiefly concerned with the recovery of unsaponifiables, particularly sterol and glycosides including sterol glucosides.

While glyceride oils usually contain between 1 and 2% unsaponifiables, many of which can be isolated and identified by laboratory analytical procedures, it is extremely difilcult to recover these materials in commercial quantities and concentration either from the crude or refined oils or from the gums or soap stock removed from the oil during refining. Because of the large amounts of materials which must be handled and the difilculty with which the unsaponifiables are separated from these materials, such operations as solvent extractions, etc., are expensive and time consuming.

An initial degumming operation results in the separation from the oil of a material consisting predominantly of phosphatides and usually containing in the neighborhood of 3% unsaponifiables. These unsaponifiables are, however, largely intimately bound up with the gummy materials, including phosphatides, and it is difficult to recover the same. Such recovery steps also usually destroy the valuable phosphatides. The degumming operation, however, does not remove all of the-unsaponifiables from the oil, and in general this is true of all of the usual refining operations conventionally practiced upon glyceride oils. For example, a conventional caustic alkali refining step, either a batch or a continuous operation, usually leave in the'neighborhood of 1% unsaponifiables in the oil although a considerable amount of unsaponifiables is separated with the soap stock. This is true irrespective of whether 2 r r i the oil has been subjected to a prior degumming step. A greater amount of unsaponifiable is present in the soap stock when no prior degumming operation hasbeen carried out since the phosphatides with their associated -unsaponifiables are also present in the soap stock. In any case the unsaponifiables separated in the soap stock are also difiicult to recover because of the large amount of other materials such as soap or gum present. The unsaponifiables left in the oil fter a caustic alkali refining step appearto be intimately bound up with the oil and are also extremely difiicult to remove therefrom.

While alkali refining steps employing soda ash or other non-saponifying alkalies also cause removal of a considerable amount of unsaponifiables in the soap stock in difiicultly recoverable form, it i an unexpected fact that such nonsaponifying alkali 'efining treatments remove a substantially less amount of unsaponifiables from the oil than caustic alkali treatments and that a substantial portion ofthe unsaponifiables left in the oil is'rather easily removable therefrom and can be recovered in concentrated form. Thus, aqueous agents, including pure water, can be employed to remove a portion of the unsaponifiables left in the oil after a soda ash or similar refining step with non-saponifying alkalies, and these unsaponifiables may be recovered in extremely concentrated form with a minimum of contamination with other materials. Separate recoveries of difierent types of unsaponifiables can also be obtained by employing different types ofagents in succession on the oil. It should be apparent from the above that it is not the actual concentration of the unsaponifiables in the oil at any given time during a refining operation which is of primary importance, but that it is the condition of the oil and unsaponifiables in the oil at the time of the recovery treatment which enables the recovery of unsaponifiables in concentrated form and in a form in which they may be readily purified.

It is, therefore, an object of the present invention to provide an improved process of refining glyceride oils and recovering unsaponifiables therefrom.

Another object of the invention is to provide a process of recovering unsaponifiables from glyceride oils in which the oil and unsaponifiables are conditioned for separation of said unsaponifiables and the unsaponifiables are recovered in concentrated relatively pure form during a refining operation.

Another object of the invention is to provide a method of recovering unsaponifiables from glyceride oils in which an oil, after treatment with a non-saponifying alkali and removal of the soap stock therefrom, is treated with an aqueous agent to recover unsaponifiables.

A further object of the invention is to provide a process in which a separation between various types of unsaponifiables may be produced during The unsaponifiables have also been defined as all unsaponifiable substances which are insoluble in water but soluble in light petroleum ether. The unsaponifiables comprise a mixture of extremely complex substances. They contain carotinoid pigments, vitamins A, D, K and E, sterols, hydrocarbons, inhibitols, tocopherols and combinations of certain of these substances with carbohydrates, as wellas other materials some of which are unidentified. Vitamin E or alpha tocopherol is present in crude vegetable oils to the extent of from 0.1 to 0.2% and is a particularly valuable byproduct recovered in accordance with the present invention. The tocopherol content of the unsaponifiable material recovered by the present invention may range from approximately 5 to 33%. Sterols also represent valuable byproducts and are usually present in the recovered material as free sterols, as sterol esters, and as sterol glucosides. Free sterols can be obtained from the esters and glucosides by acid hydrolysis thereof, although the sterol glucosides themselves have important uses. They are excellent emulsifiers, particularly when employed in conjunction with other emulsifying or wetting agents. The present invention furnishes an important source of such glucosides.

In carrying out the present invention, substantially all of the gummy materials, including phosphatides, and substantially all of the free fatty acids are first removed from the glyceride oil by an alkali refining operation employing soda ash or other non-saponifying alkali as a neutralizing agent. A degumming operation may or may not be employed prior to the alkali refining operation. In general, the-recovery of unsaponifiables will be somewhat greater :when no prior degumming operation is employed, but this is at the expense of separating the valuable phosphatides in admixture with the soap stock from the alkali refining operation. Since the gums are removed from the oil in either a degumming step or the alkali refining step, the unsaponifiables recovered in the present invention are not substantially contaminated by gummy materials. The soda ash or similar refining step appears to conditionthe unsaponifiables for easy removal. It is apparent that this is the case, as an oil which has merely been degummed is not susceptible to treatment for the removal of unsaponifiables by the aqueous treatment step of the present invention until after it has been subjected to a refining operation with a nonsaponifying alkali.

The preferred non-saponifying alkali for conditioning of the oil in accordance with the pres- Lil - carbonate.

ent invention is soda ash, although other nonsaponifying alkalies, such as those mentioned in the patent to Clayton 2,249,701, granted July 15, 1941 can be employed. Examples of such other non-saponifying neutralizing agents are disodium phosphate, trisodium phosphate and equivalent potassium salts, including potassium The refining operation of said patent, including dehydrating and rehydrating steps as disclosed therein, is also the preferred type of alkali refining operation, although simpler procedures using non-saponifying neutralizing agents may be employed, such as that disclosed in Clayton Patent 2,190,594, granted February 13, 1940. Thus, substantially any primary refining operation or operations employing nonsaponifying alkalies so as to reduce the fatty acid and gum contents to low values, while leaving a substantial amount of recoverable unsapom'fiables in the oil may be practiced in accordance with the present invention. In general, continuous processes, particularly that shown in Clayton 2,249,701, produce oils having the highest recoverable unsaponifiables content, but the present invention is not limited to such continuous process for primary refining.

In accordance with the present invention, it has been found that a portion of the unsaponifiable content left in the oil after an alkali refining step with a nonsaponifying alkali can be removed by mixing water with the oil and subjecting the resulting mixture to continuous centrifugal separation. The heavier efliuent is predominantly water, but carries out of the oil a substantial quantity of unsaponifiables, which action is unexpected as the unsaponifiables are substantially insoluble in water. In fact, the unsaponifiables tend to separate from the water during centrifugal separation to form an intermediate layer between the water and the oil. That is to say, the mixture stratifies into three layers in the centrifugal. It is'difficult to adjust a continuous centrifugal separator so that'the layer of unsaponifiables is discharged with the water as the heavy effluent, since a portion of the unsaponifiables of this layer tend to come out with the oil layer and a portion with the water. Such stratification can be largely prevented by employing relatively large amounts of water, for example, amounts of water between 19 and of the oil. However, when water is mixed with oil with sufficient intensity to cause the unsaponifiables to separate with the water, inevitably a small amount of oil is emulsified in the water so that such large amounts of water tend to cause losses of valuable neutral oil. This loss can, to a large extent, be overcome by employing a small amount of water in the initial admixture of water with the oil, for example 1 to 5%, and then adding a larger amount of water to the oil in a loose mixture just prior to the centrifugal separation operation. In such cases, 5 to 35% additional Water will ordinarily cause substantially'complete separation of the unsaponifiables with the water without material loss of oil.

In fact, it has been found unnecessary to add the additional water to the oil and water mixture entering the centrifugal so long as the additional water is present in the centrifugal separator during separation. Thus, the additional water may be added to the heavier eifluent in the centrifugal just after separation of the water from the oil, for example, in an apparatus such as shown in Clayton application Serial'No. 483,953, filed April 21, 1943. Introducing the additional water just before or during the actual separation in the centrifugal produces a somewhat improved operation. A particularly efiective apparatus for this purpose is that disclosed in Clayton Patent No. 2,301,110, granted November 3, 1942, in which the water is added at or Just inside the neutral zone of separation in the centrifugal so that any uns'aponiiiabies which tend to come out with the oil are washed from the oil into the aqueous phase and are carried out as Part of the heavy emuent.

No difficulty is encountered in separating the unsaponifiables from the heavier eiliuent from the centrifugal separation just discussed. These unsaponifiables collect as an upper layer when the separated heavy effluent is allowed to stand, and can be removed therefrom by decantation, skimming, etc. It is also possible to immediately run the heavy eliiuent through a second. continuous centrirugal separator correctly adjusted so that a lighter effluent is discharged which is predominantly unsaponinables, and a heavier eiiluent discharged which is substantially free of unsaponiriables.

It has been found that an increased recovery of unsaponiiiables is attained if the water used to remove the unsaponiiiaoles is made acidic, for example by adding acids which ionize to a substantial extent such as mineral acids, salts of strong acids and weak bases, or even strongly ionizing organic acids such as acetic acid. In general, a small amount of acidity, i. e., even a slight lowering of the pH of the water, causes a considerable increase in the amount of unsaponiiiables. Relatively strong acid solutions may also be employed, but have the disadvantage that they impart acidity to the neutral oil which is diflicult to remove without a subsequent alkali treatment. As discussed below, such subsequent alkali refining operations are in some cases dosirable to remove additional unsaponifiables, in which case relatively strong acids may be employed in the first unsaponiiiables-removal step.

When aqueous acid solutions are employed to remove the unsaponifialoles, even slightly acid solutions tend to raise the acidity of the oil. This can be overcome by employing a slightly alkaline solution as a flush in the centrifugal to prevent stratification of the unsaponifiables and carry the same out of the centrifugal with the heavier eiliuent. Addition of the alkaline solution to the heavier efiiuent in the centrifugal after it has been separated from the oil has some effect in reducing this acidity, but it is preferred to add the alkaline solution in the zone of separation, preferably slightly inside of the neutral zone; for example, by the apparatus disclosed in Clayton Patent No. 2,301,110 referred to above. When using acid aqueous agents the amount of precipitating or extracting agent and the amount of additional liquid added to the centrifugal will in general fall within the ranges above given when employing neutral or pure water.

It is also possible to increase the amount of unsaponifiables recovered over that recovered when a neutral water is employed by, employing a caustic alkali solution such as a solution of sodium hydroxide. Such alkaline solutions are particularly desirable when the oil being treated is a highly colored oil such as cottonseed oil or palm oil. Strong caustic alkali solutions can be employed to remove coloring materials which themselves fall under the broad classification of unsaponifiables. The best removal of color is usual amounts being between 10 and 20%.

ordinarily obtained with highly concentrated caustic alkali solutions, for example, solutions between 16 and 50 Be. caustic alkali, although in some instances weaker solutions ranging between 5 and 16 Be. may be employed. Even weak or slightly alkaline solutions will remove a substantial amount of unsapcnifiables, but ordinarily are not effective color-removing agents. The stratification problems referred to above when employing neutral water or slightly acidic solutions also occur when alkali solutions are employed, and this is particularly true both with an extremely strong alkali solution and very weak alkali solutions. In such cases, additional water can be added to the mixture of oil and alkaline solution just prior to centrifugal separation or during centrifugal separation, as described above, addition during centrifugal separation being preferred. That is to say, amounts of alkaline solution between 1 and 5% are ordinarily added in the initial mixing step and then additional amounts of aqueous agent, for example, between 5 and 35% are added as a flushing agent, the In general, adding the diluting or flushing agent just inside and close to the neutral zone in the centrifugal (for example, in the apparatus disclosed in Clayton Serial No. 483,953, filed April 21, 1943) requires the least amount of flushing solution. In some cases neutral water is adequate for such flushing solution, but weakly alkaline solutions are desirable where acid solutions have been employed as the precipitating agent and sometimes it is desirable to add weak acid solutions where acidity in the final oil is not deleterious since such acid solutions facilitate the separation of the unsaponifiables from the heavier effluent.

It should be apparent from above that neutral water or acid precipitating solutions, in general, do not remove much of the coloring matter and that there is a difference between the unsaponifiables removed by water, by acid solutions and by caustic alkali solutions. For light colored oils, for example, corn oil, water alone removes most of the unsaponifiables which are present in the oil in removable form. Acid solutions remove more of the unsaponifiables and the same is true of alkali solutions although the additional unsaponiflables removed by alkali solutions will usually differ from those removed by acid solutions. It is possible to first employ a removal operation using water or weak acid or alkaline solutions, and then subsequently treat the oil with a caustic alkali solution to obtain additional unsaponifiables. In the case of highly colored oils such as cottonseed oil, a first treatment with water or weak acid or weak alkaline solutions does not remove a substantial amount of the coloring material, and a subsequent treatment with a strong alkali does remove a substantial amount of unsaponiiiables including carotinoid pigments, etc. It will be apparent that two successive treatments as discussed above can be employed to remove light colored unsaponifiables, including the greater portion of the sterols and sterol glucosides, and then a caustic alkali treatment can be employed to remove carotinoids, tocopherols, etc. It is further apparent that the strong caustic can be employed initially to remove substantially all of the unsaponifiables, in which case the various types of unsaponifiables are recovered in admixture and require extensive subsequent separation steps, which are many times diflicult toperform.

17 flit is furthen apparent.xfromithewabove that a large number of electrolytes may be employed in iconjunction "with Water, or Water :alone may be .i employed as a an unsaponifiableeremoving agent after the oil hasbeen-conditioned bya proper refinin operation to condition the unsaponifiables for separation. Thus, :acids, including mineral acids such as hydrochloric and sulfuric, maybe employed, various salts either neutral, basic or acidic may be employed, aswell. as strong alkalies. Among the alkaline agents possibleito be employed are sodiumphosphate, sodiumv pyrophosphate, lithium hydroxide, potassium hydroxide, sodium borate, borax,-sodium; peroxide, etc. 'Even substantially neutral salts such as sodium sulfate or sodium chloride insome cases increase the amount of unsaponifiables recovered over pure water. Thus substantially any aqueous solution of an electrolyte or pure water is contemplated as an unsaponifiables-removing agent. Various agents can be used in succession to obtain' difierent types of unsaponifiables although a large number of treatments of all of the oil is in general uneconomic.

When neutral or acidic or even slightly alkaline solutions are employed as the unsaponifiables-removing'agent, no difficulty is encountered inseparating the unsaponifiable from the solution after separation from the oil. However, when strongly alkalinesolutions are employed, particularly when these strong alkaline solutions are diluted during separation from the oil, the unsaponifiables tend toremain in suspension in the aqueous 'material. This tendency can be overcome by slightlyacidulating the heavy effluent either in the centrifuge as above mentioned or thereafter. This acidulation need not be and preferably is not sufficient to decompose the small amounts of soap formed due to treating the oil withstrong alkalies, since decomposing the soap formed due to treating the oil with strong alkalies, since decomposing the soap liberates free fatty acids which would be separated with the unsaponifiables. It has been found that sufficientacid, such as a mineral acid or relatively strong organic acid, can be added to the aqueous effiuent of the centrifugal to'render te unsaponifiables separable and at the same time leave the soap substantially undecomposed, so that the soap remains in. solution in the aqueous phase. Alternatively acidulation ofthe heavier eflluent can be preformed later-as part of the step of separating the unsaponifiables from the aqueous heavier eiliuent.

As indicated above, the oil, after separation of unsaponifiables in. relativelypure form as discussed above, still contains a substantialamount of unsaponifiables which are apparently extremely intimately bound up with the oilitself. It is possible torecover certain of these unsaponifiables by treatment of the oil' with an adsorbent such as activated alumina, silica gel, synthetic resins, etc., and filtering the oil from the filter cake. The-filter cake can thenbe extracted with acetone, alcohol or ether toremove the unsaponifiables. Instead of filtering it is also possible to centrifugally separate the adsorbent carrying the unsaponifiables from the oil in a batch type of centrifugal, or this material may be separated in-a continuous centrifugal separator with theaid of a stream offflush material directed into the bottom of the-centrifugal bowl and outwardly to the walls thereof. so as to wash the solid adsorbent out of the :cen- 'trifu'gal. The solid'adsorbent canthen be deccanteid ors'filtered from 1 the r aqueous phase I treated with solventsas above described. Such an operation can even beemployed for separat- ..ing an .of the unsaponifiables after the non- 5 saponifying alkali refining step, but ingeneral is not aseilectiveor as easily, .performed as the operations described above. Nevertheless, such adsorbent treatment can .sometimes'be carried .outlas a practical operation after treatment with .10 aqueous solutions as above described to, recover still another type of unsaponifiables.

As the soda ash. or similar non-saponifying refining step contemplated in the present invention does remove a substantial amount of un- :15. saponifiables, it is advantageous to use the minimum possible amount of refining agent which can be employed to produce a neutral 6il and provide eliec'tive separation of soap-stock. In other words, minimizing the reagent in the .20 alkali refining step results in an increased recovery of unsaponifiables in the subsequent recovery steps. Also, as indicated above, maximum recovery of unsaponifi'ables is accomplished when no 'degumming step is employed prior to'the .25 alkali refining step, so that the phosphatides with their associated unsaponi'fiables are present during the treatment of the oil'with the nonsaponifying alkali in the refining "step.

It willthus be seen that the present invention .30, provides for the recovery of a concentrate'high in unsaponifiables from glyceride oils as a result of the conditioning of these oils'for separation of the unsaponifiables by a refining-operation employing a non-saponifying alkali, 'whichrefining operation is of the-type in"whichthe losses of neutral o'il arereduced to almost a'theoretieal minimum. "Theunsaponifiables recovered are valuable products'commanding'a high price on the market. They constitute an "excellent --.40 source of vitamins, sterols an'd'sterol"glucosides.

These various materialspan "be re-latively easily individually "separated from the concentrate by solvent extraction or distillation operations; and this is particularlytruewherethe *morehighly 5 colored unsaponifiables' such as carotin xanthophyllsand;'chlorophylls I are separated from other unsaponifiables predominantly sterols and sterol compounds during the recovery process. The "carryingoutof the present process enablesahigh ai=so-quality ofedible refined oilto he produced and adds "substantially no- -ex-pense --tothe refining process. The material recovered from the heavier effluent -whenvia/ter or slightly acidic: or al- ""aline --solutions are employed runs extremely .35 high in unsaponiiiables which are predominantly --materials beingsoap washed from the-oil-anda small amount of gums-not removed in degum- 'ming or the prior alkali :refinin operation. 'When strong caustic alkali is'em-ployed .in the unsaponifiables removal step, substantially :c5- greater amountsof soap are: present, .but even *so' this material may. runes i high as 75% .unsapomfiables. Substantiallyiili) concentrations of-unsaponifiables may be produced from. any I of these materia1s-lby one or -more successive 70 solventtreatments, for example, with petroleum ether, acetoneor othersolvent.

The process of l the present invention is. preferably carried outin acontinuous manner. That is-tosay: thelrefining'. stepssor: steps for conditioning the 1 oil may be operative in which-fl-the oil and agents are mixed in continuous stream. flow and separations of soap stock or fonts from,

the oil are carried out in continuous centrifugal separators. The mixing of the agent for rendering the unsaponifiables separable is also preferably carried out in stream flow by bringing proportioned streams of oil and agent together in a mixer and the resulting mixture delivered as a stream to a continuous centrifugal separator. When employed, a stream of dilutin or flushing agent may be delivered into the stream of mixture entering the centrifugal or delivered directly into the centrifugal as above described. Thev stream of the resulting heavier eirluent may be directly delivered to a secondcentrifugal for,

further concentrating the unsaponifiables or concentration may be effected by settling and.

decantation.

Whil I have disclosed the preferred embodiments of my invention, it is understood that the details thereof may be varied within the scope o the following claims.

Iclaim: 1. The process of refining glyceride oils and recovering unsaponifiables therefrom, which comprises subjecting a glyceride oil containing unsaponifiables to a neutralizing step employing a non-saponifying alkali and including the separation of soap stock from neutral ch in order to condition the glyceride oil for separation of unsaponifiables therefrom, thereafter mixing the separated neutral oil with an aqueous agent which will render unsaponifiables separable from said neutral oil, separating said aqueous agent along with unsaponifiables from the resulting oil and separating unsaponifiables from the separated aqueous agent.

2. The process of refining glyceride oils and recovering unsaponifiables therefrom, which comprises subjecting a glyceride oil containing unsaponifiables to a neutralizing step employing soda ash and including the separation of soap stock from neutral oil in order to condition the glyceride oil for separation of unsaponifiables therefrom, thereafter mixing the separated neutral oil with an aqueous agent which will cause unsaponifiables to be separable from said neutral oil, separating said aqueous agent alon with unsaponifiables from the resulting oil and sep arating unsaponifiables from the separated aqueone agent. 3. The process of refining glyceride oils an recovering unsaponifiables therefrom, which comprises subjecting a glyceride oil containing unsaponifiables to a neutralizing step employing a nonsaponifying alkali and including theseparation of soap stock from neutral oil in order to condition the glyceride oil for separation of unsaponifiables therefrom, thereafter mixing the separated neutral oil with an aqueous agent which will render unsaponifiables separable from said neutral oil continuously centrifugally separating said aqueous agent along with unsaponifiables from the resulting oil and separating unsaponifiables from the separated aqueous agent.

4. The process of refining glyceride oils and recovering unsaponifiables therefrom, which comprises subjecting a glyceride oil containing unsaponifiables to a neutralizing step employing a non-saponifying alkali and including the separation of soap stock from neutral oil in order to condition the glyceride oil for separation of unsaponifiables therefrom, thereafter mixing the separated neutral oil with a small amount of aqueous agent which will render unsaponifiables separable from the neutral 0il,.,continuously centrifugally, separating saidaqueous agent along with unsaponifiables from the resulting oil, adding an additional amount of aqueous agent to the centrifugal separator'so as to mix with the heavier effluent therein to, facilitate separation of said unsaponifiables with said heavier efliuent, and separating,unsaponifiables from the heavier effluent discharged from's aid centrifugal.

5. The process of refining glyceride oils and recovering unsaponifiables therefrom, which comprises subjecting a glyceride oil containing unsaponifiablesto a neutralizing step employing a non-saponifying alkali and. including the separation of soap stock from neutral oil in orderto condition the glyceride oil for separation of unsaponifiables therefromjthereafter mixing the separated neutraloil with a small amount of aqueous agent .which will cause unsaponifiables to be separable from the neutral oil, continuously centrifugally separating said aqueous agent as a condition the glyceride oil for separation of unsaponifiables therefrom, thereafter mixin the separated neutral oil with sufficient water to cause said unsaponifiables to be separable with said water, continuously jcentrifugally separating said Water al0ng.with unsaponifiables from theresuiting oil, arid separating unsaponifiables from the separated water.

7. The processor refining glyceride oils and recovering unsaponifiables therefrom, which comprises subjecting a, glyceride oil containing unsaponifiablestoa neutralizing step employing a non-saponifying alkali and including the separation of soap stockfromneutral oil in order to condition the glyceride oil for separation of unsaponiflables therefrom, thereafter mixing the separatedneutral oilwith an aqueous; alkaline agent which will-render unsaponifiables separarable from, the neutral oil, continuously centrifugally separating said aqueous alkaline agent along with unsaponifiables from the resulting oil, and separating unsaponifiables from the separated agent.

3. The process of refining glyceride oils and recovering unsaponifiables therefrom, which comprises subjecting; a glyceride oil containing uns'aponifiables to a neutralizing step employing a non-saponifying alkali and including the separation of soap stock from neutral oil in order to condition the glyceride oil for separation of unsaponifiables therefrom, thereafter mixing the separated neutral oil with a concentrated solution of caustic alkali to cause unsaponifiables to be separable from the neutral oil, continuously centrifugally separating said agent along with unsaponifiables from the resulting oil, diluting said agent during centrifugal separation with an aqueous medium to assist in separation of said unsaponiflables with said agent, and separating unsaponifiables from the separated. agent.

9. The process of refining glyceride oils and re- 11? covering, unsaponifi'ables therefrom, ,which'comprises subjectinga glyceride1oilfcontaining un-' saponifiables to a neutralizing step .employing'a.

non-saponifying .alkali and'including the separationlofsoap stock from neutral'oil in order to condition. the glyceride oil fort separationof. un1- saponifi'ables therefrom, thereafter mixing the separated neutral .oil" with an aqueous aCidQ SOhl-r tion. to; cause. unsaponifiables tob'e' separable" from i the neutral oil, .continuously centrifugally separating said acid. solution alon i'jwith' unsaponifiahles from. the. resulting oil; thereafter mixing the resulting oiljwithl an alkali" solution to causelunsappnifiables,to'be separable from the resulting oil .andicontinuously centrifugally; separating said alkali solution along withlunsapom ifi'ab1s...from, the resulting, oil; and separating unsaponifiables iromboth the, separated acidsoluti'on. and the separated alkalij 'solution.

10.' The. process, ofqlrefining glyceride' oil's and recovering ,unsaponifi'ables therefrom, which-com prises subjecting a glyceride' oil 'gcontainingunsaponifiables to a. neutralizing" step" employing a sodaash. as a neutralizing agent and'including the. separation ofgsoap stock from neutral oilin orderitocondition theresultingoil Lfor'separation ofjlunsaponifiables, thereafter mixing .the conditioned oil with a small amountof aqueous-acid agent which will, render unsaponifiables separable" from the neutral.v oil, continuously centrifugally separating saidi'aqueous agent asaheavier-eflim entlalong. with .unsaponifiablesfrom the' result-' in .oil;,introducing;ian amount ofaqueous-alkaline; agent into, the. centrifugal separator' adjacent the,v neutral zone of separation therein to assist in. separating, said unsaponifiables with said, heavier effluent and: neutralize acidity in the. resulting oil, and separating unsaponifi'ables from the separated heavier eflluent.

111mm process or; refining gl oils recovering, un'saponifiables. therefrom; which comprises subjecting a' glyceride oilcontaining;

unsaponifiables. to. .a..neutralizingijstep employing soda. ash as. a.ne11tralizing. agentv and including the separation. of soapstock from neutral oil in order. to. conditiontthe, glyceride. oil 5 for, separation. of; unsap-onifiables, thereafter. mixing the separated neutral oil. withwsufiicientwater to cause: said: un-saponifiables, to, lie/separable {with said water, continuously centrifugally. separating; said. Wateralong with unsaponifiablesfroml the resulting oil, and. separating .unsaponifi'ab'les from. theseparated water.

12.- The z-process. 0t refining glyceride oils, and. recovering; unsaponifiables: therefrom, which.

comprises subjecting: as glyceride oil containing unsaponifiables to a neutralizing step. employing soda. ash.as-the-neutralizing:agent and including therseparation of soap stockflom neutral.

oil. in order to condition. the. glyceride oil. for

separationofnunsaponifiables, thereafter mixing.

the separated neutral :oil' with an aqueous. agent which will cause unsaponifiables to be separablefrom the'neutral oil, continuously centrifugally separating said aqueous agent asa heavier effluent along with unsaponifiables from theresultingoil and separating unsaponifiables from the separated heavier eflluent by subjecting-said heavier efiiuent to a second continuous centrifugal separation. v

13. The processof refining glycericle oils and recovering unsaponifiables therefrom, which comprises subjecting, a glyceride oil containing unsaponifiables to a neutralizing; step employing a non-saponifying alkali including the separation of soap stock from neutral oil in order to condition the glyceride oil for separation of unsaponifiables, thereafter mixing the separated. neutral oil with an aqueous alkaline'agent whichwill render unsaponifiable-s separable from the neutral oil, continuously centrifugall'y separating said aqueous alkaline agent as .a heavier. ef-

present therein and wherein theresulting soapstock is separated from theoil, theimprovement which comprises the steps of adding an agentto said refined oil which will renderunsaponifiable material remaining in the oil separable Without destruction of the oil, separating a material containing unsaponifiable material from the oil and separating unsaponifiable material from. the separated material.

15. The process of refining glyceride' oils and recovering glucosides therefrom, which comprises subjecting a glyceride oil containin glucoside' to a neutralizing step employing a non-saponifiable alkali and includingv the separation of 1 soap, stock from neutral oil in order to condition theglyceride oil for separation of said glucoside,

thereafter mixing the separated neutral oil with an aqueous agent which Will render glucosides separable from said 011,, separating said aqueous agent along with glucosides from the resulting oil and separating glucosides from the separatedaqueous agent. I

MORRIS MATTIKOW.

REFERENCES CITED Thefollowing references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date.

2,249,701 Clayton July 15, 1941 2,306,547 Langlois Dec. 29, 1942 Dedication 2,415,301.-Zl [0rm's 111 attz'icow, New York, N .Y. REFINING OF GLYCERIDE OILS AND RECOVERY OF BY PRODUCTS. Patent dated Feb. 4, 1947. Dedication filed June 30, 1964, by the assignee, Benjamin Ulayton, doing business as Refim'n U nincowpomted.

Hereby dedicates to the public the terminal part of the term of said patent effective December 31, 1963.

[Oficz'al Gazette Septembew 29, 1.964.] 

